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G6Tanuki · 14th Nov 2017, 3:32 pm

It'll work just fine, but will, as others have noted, be a bit more lossy than a single transformer.

In a previous existence I used 2 back-to-back transformers this way to power a US-made battery-valve portable radio: the 2 transformers I used both had 9V secondaries and I was happy to 'steal' 50mA from the back-to-back secondaries to be rectified and provide the floating 7.5V heater supply [five 1.4V valves in series].

The second transformer had a 9v primary and US-style 110-120V secondary which again rectified nicely to provide the 120V B+ supply.

14th Nov 2017, 3:32 pm	#4
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 13,998	Re: 'Alternative' isolation transformer It'll work just fine, but will, as others have noted, be a bit more lossy than a single transformer. In a previous existence I used 2 back-to-back transformers this way to power a US-made battery-valve portable radio: the 2 transformers I used both had 9V secondaries and I was happy to 'steal' 50mA from the back-to-back secondaries to be rectified and provide the floating 7.5V heater supply [five 1.4V valves in series]. The second transformer had a 9v primary and US-style 110-120V secondary which again rectified nicely to provide the 120V B+ supply.